A U.S. Fish and Wildlife Service volunteer corps is planting native flowering plants, most notably milkweed, which is crucial for the survival of monarch butterflies. Monarchs lay their eggs in milkweed, which provides essential nutrition for the larvae. Milkweed has disappeared across the nation—and with it, monarch populations have crashed since the 1990s, down 75 percent or more.
The situation is especially dire for Western monarchs. Cheryl Schultz, an associate professor at Washington State University in Vancouver, was the lead author of a study that found that compared to the 10 million monarchs that overwintered in coastal California in the 1980s, today there are barely 300,000. That’s a trajectory that points to extinction.
While pesticides, logging, development and climate change probably all play a role, key to the butterfly’s annihilation is the loss of milkweed habitat.